Tension-torsion strap

Patent metadata

Field	Value
Publication number	US-10988243-B2
Application number	US-201916354421-A
Country	US
Kind code	B2
Filing date	Mar 15, 2019
Priority date	Mar 15, 2019
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

A tension-torsion strap, for example for a rotor aircraft, including a continuous length of carbon fiber tow arranged in multiple loops to form an elongated member extending between opposing ends and a flexible cover encasing the carbon fiber tow.

First claim

What is claimed is:

1. A tension-torsion strap couplable between a rotor blade and a hub assembly of a rotor aircraft, the tension-torsion strap comprising:
A single carbon fiber tow that forms an elongated member;
a fastener at each of two opposing ends of the elongated member to couple the tension-torsion strap between the rotor blade and the hub assembly;
a flexible cover encasing the elongated member; and
wherein the single carbon fiber tow consists of a single continuous length of carbon fiber.

2. The tension-torsion strap of claim 1 , wherein the flexible cover is constructed of urethane.

3. The tension-torsion strap of claim 1 , wherein the continuous length of carbon fiber tow is arranged in multiple loops to form the elongated member.

4. The tension-torsion strap of claim 3 , wherein the flexible cover is constructed of urethane.

5. The tension-torsion strap of claim 3 , wherein the carbon fiber tow consists of a single continuous length of carbon fiber tow.

6. The tension-torsion strap of claim 1 , wherein each of the fasteners is an aperture.

7. The tension-torsion strap of claim 3 , wherein the multiple loops are arranged parallel to one another.

8. The tension-torsion strap of claim 3 , wherein the multiple loops form two parallel extending legs that are laterally separated by a gap, each of the legs are separately encased in the flexible cover.

9. The tension-torsion strap of claim 8 , further comprising a web extending across the gap and interconnecting the two parallel extending legs.

10. A tension-torsion strap for a rotor aircraft, the tension-torsion strap comprising:
a single continuous length of carbon fiber tow arranged in multiple loops to form an elongated member extending between opposing ends;
a flexible cover encasing the carbon fiber tow, the flexible cover constructed of urethane;
wherein each of the opposing ends comprises a fastener; and
wherein the fastener is an aperture.

11. The tension-torsion strap of claim 10 , wherein the multiple loops form two parallel extending legs that are laterally separated by a gap, each of the legs are separately encased in the flexible cover.

12. The tension-torsion strap of claim 11 , further comprising a web extending across the gap and interconnecting the two parallel extending legs.

13. A rotor system for a rotor aircraft, comprising:
a rotor blade;
a hub assembly; and
a tension-torsion strap coupled to the hub assembly and coupled to the rotor blade,
wherein the tension-torsion strap comprises:
a continuous length of carbon fiber tow arranged in multiple loops to form an elongated member extending between opposing ends; and
a flexible cover encasing the carbon fiber tow.

14. The rotor system of claim 13 , wherein the multiple loops are arranged parallel to one another.

15. The rotor system of claim 13 , wherein the carbon fiber tow consists of a single continuous length of carbon fiber tow.

16. The rotor system of claim 13 , wherein the carbon fiber tow consists of a single continuous length of carbon fiber tow; and
the multiple loops are arranged parallel to one another.

17. The rotor system of claim 16 , wherein the multiple loops form two parallel extending legs that are laterally separated by a gap, each of the legs are separately encased in the flexible cover.

Assignees

• Bell Textron Inc

Inventors

• Haldeman Andrew Paul
• Miller Gary

Classifications

• B29K2075/00

  Use of {PU, i.e.} polyureas or polyurethanes {or derivatives thereof}, as moulding material · CPC title

• B64C27/35

  having elastomeric joints · CPC title

• B64C27/48

  Root attachment to rotor head · CPC title

• B32B2262/101

  Glass fibres · CPC title

• B32B27/12

  next to a fibrous or filamentary layer · CPC title